Abstract: The semiconductor device includes a first layer including a first transistor, a second layer including a first insulating film over the first layer, a third layer including a second insulating film over the second layer, and a fourth layer including a second transistor over the third layer. A first conductive film electrically connects the first transistor and the second transistor to each other through an opening provided in the first insulating film. A second conductive film electrically connects the first transistor, the second transistor, and the first conductive film to one another through an opening provided in the second insulating film. A channel formation region of the first transistor includes a single crystal semiconductor. A channel formation region of the second transistor includes an oxide semiconductor. The width of a bottom surface of the second conductive film is 5 nm or less.

Abstract: A semiconductor device having favorable electrical characteristics can be provided. The semiconductor device having favorable electrical characteristics is provided.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device includes a transistor and a capacitor. The transistor includes a first conductor and a second insulator over a first insulator; a third insulator over the first conductor and the second insulator; a fourth insulator over the third insulator; a first oxide over the fourth insulator; a second oxide and a third oxide over the first oxide; a second conductor in contact with a top surface of the third insulator, a side surface of the fourth insulator, a side surface of the first oxide, a side surface of the second oxide, and a top surface of the second oxide; a third conductor in contact with the top surface of the third insulator, a side surface of the fourth insulator, a side surface of the first oxide, a side surface of the third oxide, and a top surface of the third oxide; a fourth oxide over the first oxide; a fifth insulator over the fourth oxide; and a fourth conductor over the fifth insulator.

Abstract: The semiconductor device includes a first layer including a first transistor, a second layer including a first insulating film over the first layer, a third layer including a second insulating film over the second layer, and a fourth layer including a second transistor over the third layer. A first conductive film electrically connects the first transistor and the second transistor to each other through an opening provided in the first insulating film. A second conductive film electrically connects the first transistor, the second transistor, and the first conductive film to one another through an opening provided in the second insulating film. A channel formation region of the first transistor includes a single crystal semiconductor. A channel formation region of the second transistor includes an oxide semiconductor. The width of a bottom surface of the second conductive film is 5 nm or less.

Abstract: A semiconductor device with small fluctuations in transistor characteristics can be provided. The semiconductor device includes a first oxide, a second oxide and a third oxide over the first oxide, a first conductor over the second oxide, a second conductor over the third oxide, a fourth oxide over the first oxide and between the second oxide and the third oxide, a first insulator over the fourth oxide, and a third conductor over the first insulator. The first oxide includes a groove in a region not overlapping with the second oxide and the third oxide. The first oxide includes a first layered crystal substantially parallel to the surface where the first oxide is formed. In the groove, the fourth oxide includes a second layered crystal substantially parallel to the surface where the first oxide is formed. A concentration of aluminum atoms at an interface between the first oxide and the fourth oxide and in the vicinity of the interface is less than or equal to 5.0 atomic %.

Abstract: A semiconductor device in which a variation of transistor characteristics is small is provided. The semiconductor device includes a transistor. The transistor includes a first insulator, a first oxide over the first insulator, a first conductor, a second conductor, and a second oxide, which is positioned between the first conductor and the second conductor, over the first oxide, a second insulator over the second oxide, and a third conductor over the second insulator. A top surface of the first oxide in a region overlapping with the third conductor is at a lower position than a position of a top surface of the first oxide in a region overlapping with the first conductor. The first oxide in the region overlapping with the third conductor has a curved surface between a side surface and the top surface of the first oxide, and the curvature radius of the curved surface is greater than or equal to 1 nm and less than or equal to 15 nm.

Abstract: A semiconductor device having a high on-state current is provided. The semiconductor device includes a first oxide; a first conductor and a second conductor provided over the first oxide to be separated from each other; and a second oxide provided over the first oxide and between the first conductor and the second conductor. Each of the first oxide and the second oxide has crystallinity, the first oxide includes a region where a c-axis is aligned substantially perpendicularly to a top surface of the first oxide, and the second oxide includes a region where the c-axis is aligned substantially perpendicularly to the top surface of the first oxide, a region where the c-axis is aligned substantially perpendicularly to a side surface of the first conductor, and a region where the c-axis is aligned substantially perpendicularly to a side surface of the second conductor.

Abstract: A semiconductor device having a high on-state current is provided. The semiconductor device includes a first insulator; a first oxide over the first insulator; a first conductor and a second conductor that are apart from each other over the first oxide; a second insulator covering the first insulator, the first oxide, the first conductor, and the second conductor; a third insulator over the second insulator; a fourth insulator in contact with a first conductor, a side surface of the second conductor, a side surface of the second insulator, and a side surface of the third insulator; a fifth insulator that is over the first oxide and on an inner side of the fourth insulator; a third conductor on an inner side of the fifth insulator; and a sixth insulator that is in contact with a top surface of the fourth insulator and over the third insulator, the fifth insulator, and the third conductor. The fourth insulator is divided to be apart from each other over the first oxide.

Abstract: A semiconductor device having high operation frequency is provided. The semiconductor device includes a transistor including a first conductive layer, a first insulating layer, a second insulating layer, a first oxide, a second oxide, a third oxide, a third insulating layer, and a second conductive layer that are stacked in this order, and a fourth insulating layer. The first conductive layer and the second conductive layer include a region overlapping with the second oxide. In a channel width direction of the transistor, a level of the bottom surface of the second oxide is from more than or equal to ?5 nm to less than 0 nm when a level of a region of the bottom surface of the second conductive layer which does not overlap with the second oxide is regarded as a reference.

Abstract: A highly reliable semiconductor device having a high on-state current is provided. The semiconductor device includes a first insulator, a second insulator over the first insulator, a first oxide over the first insulator, a second oxide over the first oxide, a first conductor and a second conductor over the second oxide, a third insulator over the first conductor, a fourth insulator over the second conductor, a third oxide over the second oxide, a fifth insulator over the third oxide, a third conductor that is positioned over the fifth insulator and overlaps with the third oxide, a sixth insulator covering the first to fifth insulators, the first oxide, the second oxide, and the first to third conductors, and a seventh insulator over the sixth insulator.

Abstract: A semiconductor device with high reliability is provided by the following steps: forming an oxide semiconductor; forming a first insulator in contact with the oxide semiconductor; forming a second insulator over the first insulator, forming a third insulator over the second insulator; forming an opening in the third insulator, the second insulator, and the first insulator, cleaning the inside of the opening; embedding a conductor in the cleaned opening; forming the first insulator to include an excess-oxygen region; forming the second insulator to have a higher barrier property against oxygen, hydrogen, or water than the first insulator, and processing the opening to have a cylindrical shape or an inverted cone shape.

Abstract: A semiconductor device that can have favorable electrical characteristics and can be highly integrated is provided. The semiconductor device includes a first insulator; a second insulator over the first insulator; an oxide over the second insulator; a first conductor and a second conductor over the oxide; a third insulator over the oxide; a third conductor positioned over the third insulator and overlapping with the oxide; a fourth insulator in contact with the second insulator, a side surface of the oxide, a side surface of the first conductor, a top surface of the first conductor, a side surface of the second conductor, a top surface of the second conductor, and a side surface of the third insulator; and a fifth insulator in contact with a top surface of the third insulator and a top surface of the third conductor, and a top surface of the fourth insulator is in contact with the fifth insulator.

Abstract: A highly reliable semiconductor device having a high on-state current is provided. The semiconductor device includes a first insulator, a second insulator over the first insulator, a first oxide over the first insulator, a second oxide over the first oxide, a first conductor and a second conductor over the second oxide, a third insulator over the first conductor, a fourth insulator over the second conductor, a third oxide over the second oxide, a fifth insulator over the third oxide, a third conductor that is positioned over the fifth insulator and overlaps with the third oxide, a sixth insulator covering the first to fifth insulators, the first oxide, the second oxide, and the first to third conductors, and a seventh insulator over the sixth insulator.

Abstract: A semiconductor device in which variations in characteristics, deterioration of elements, and abnormality in shape are inhibited is provided. The semiconductor device includes a first region including a plurality of elements and a second region including a plurality of dummy elements. The second region is provided in an outer edge of the first region, and the element and the dummy element each include an oxide semiconductor. The element and the dummy element have the same structure, and a structure body included in the element and a structure body included in the dummy element are formed with the same material and provided in the same layer. The oxide semiconductor includes In, an element M (M is Al, Ga, Y, or Sn), and Zn.

Abstract: A semiconductor device that can be highly integrated is provided. The semiconductor device includes a first transistor, a second transistor, a first capacitor, and a second capacitor. The first transistor includes an oxide over a first insulator, a second insulator over the oxide, a first conductor over the second insulator, a third insulator over the first conductor, a fourth insulator in contact with the second insulator, the first conductor, and the third insulator, and a fifth insulator in contact with the fourth insulator. The second transistor includes an oxide over the first insulator, a sixth insulator over the oxide, a second conductor over the sixth insulator, a seventh insulator over the second conductor, an eighth insulator in contact with the sixth insulator, the second conductor, and the seventh insulator, and a ninth insulator in contact with the eighth insulator. The first capacitor includes an oxide, a tenth insulator over the oxide, and a third conductor over the tenth insulator.

Abstract: A semiconductor device having a high on-state current is provided. The semiconductor device includes a first insulator; a first oxide over the first insulator; a first conductor and a second conductor that are apart from each other over the first oxide; a second insulator covering the first insulator, the first oxide, the first conductor, and the second conductor; a third insulator over the second insulator; a fourth insulator in contact with a first conductor, a side surface of the second conductor, a side surface of the second insulator, and a side surface of the third insulator; a fifth insulator that is over the first oxide and on an inner side of the fourth insulator; a third conductor on an inner side of the fifth insulator; and a sixth insulator that is in contact with a top surface of the fourth insulator and over the third insulator, the fifth insulator, and the third conductor. The fourth insulator is divided to be apart from each other over the first oxide.

Abstract: A semiconductor device having favorable electrical characteristics is provided. The semiconductor device includes a first insulator; a first conductor over the first insulator; a second insulator over the first conductor; a first oxide over the second insulator; second and third conductors over the first oxide; a third insulator over the second and third conductors; a second oxide over the first oxide and between the second and third conductors; a fourth insulator over the second oxide; a fourth conductor over the fourth insulator; a fifth insulator in contact with the third insulator and the second oxide; a sixth insulator in contact with the first, second, third, and fifth insulators, and the second oxide; and a seventh insulator in contact with the fourth and sixth insulators, the second oxide, and the fourth conductor. The first, sixth, and seventh insulators each contain a silicon nitride. The fifth insulator contains an aluminum oxide.

Abstract: A semiconductor device having high operation frequency is provided. The semiconductor device includes a transistor including a first conductive layer, a first insulating layer, a second insulating layer, a first oxide, a second oxide, a third oxide, a third insulating layer, and a second conductive layer that are stacked in this order, and a fourth insulating layer. The first conductive layer and the second conductive layer include a region overlapping with the second oxide. In a channel width direction of the transistor, a level of the bottom surface of the second oxide is from more than or equal to ?5 nm to less than 0 nm when a level of a region of the bottom surface of the second conductive layer which does not overlap with the second oxide is regarded as a reference.

Abstract: A change in electrical characteristics of a semiconductor device including an interlayer insulating film over a transistor including an oxide semiconductor as a semiconductor film is suppressed. The structure includes a first insulating film which includes a void portion in a step region formed by a source electrode and a drain electrode over the semiconductor film and contains silicon oxide as a component, and a second insulating film containing silicon nitride, which is provided in contact with the first insulating film to cover the void portion in the first insulating film. The structure can prevent the void portion generated in the first insulating film from expanding outward.

Abstract: A semiconductor device having high on-state current and high reliability is provided. The semiconductor device includes, a first insulator; a first oxide over the first insulator; a second oxide over the first oxide; a first conductor and a second conductor over the second oxide; a third oxide over the second oxide; a second insulator over the third oxide; a third conductor located over the second insulator and overlapping with the third oxide; a third insulator in contact with a top surface of the first insulator, a side surface of the first oxide, a side surface of the second oxide, a side surface of the first conductor, a top surface of the first conductor, a side surface of the second conductor, and a top surface of the second conductor; a fourth insulator over the third insulator; a fifth insulator over the fourth insulator; and a sixth insulator over the third conductor, the second insulator, the third oxide and the fifth insulator.